US4802205A - Circuit arrangement for telecommunications switching systems, particularly for telephone switching systems comprising information-processing sequential logic systems and traffic measuring devices - Google Patents

Circuit arrangement for telecommunications switching systems, particularly for telephone switching systems comprising information-processing sequential logic systems and traffic measuring devices Download PDF

Info

Publication number
US4802205A
US4802205A US06/896,253 US89625386A US4802205A US 4802205 A US4802205 A US 4802205A US 89625386 A US89625386 A US 89625386A US 4802205 A US4802205 A US 4802205A
Authority
US
United States
Prior art keywords
urgency
processing
information
sequential logic
processing requests
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US06/896,253
Other languages
English (en)
Inventor
Michael Eder
Klaus Leutner
Siegfried Pohl
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Siemens AG
Original Assignee
Siemens AG
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Siemens AG filed Critical Siemens AG
Assigned to SIEMENS AKTIENGESELLSCHAFT, A CORP. OF GERMANY reassignment SIEMENS AKTIENGESELLSCHAFT, A CORP. OF GERMANY ASSIGNMENT OF ASSIGNORS INTEREST. Assignors: EDER, MICHAEL, LEUTNER, KLAUS, POHL, SIEGFRIED
Application granted granted Critical
Publication of US4802205A publication Critical patent/US4802205A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04M—TELEPHONIC COMMUNICATION
    • H04M3/00—Automatic or semi-automatic exchanges
    • H04M3/22—Arrangements for supervision, monitoring or testing
    • H04M3/36—Statistical metering, e.g. recording occasions when traffic exceeds capacity of trunks
    • H04M3/365—Load metering of control unit
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04Q—SELECTING
    • H04Q3/00—Selecting arrangements
    • H04Q3/42—Circuit arrangements for indirect selecting controlled by common circuits, e.g. register controller, marker
    • H04Q3/54—Circuit arrangements for indirect selecting controlled by common circuits, e.g. register controller, marker in which the logic circuitry controlling the exchange is centralised
    • H04Q3/545—Circuit arrangements for indirect selecting controlled by common circuits, e.g. register controller, marker in which the logic circuitry controlling the exchange is centralised using a stored program
    • H04Q3/54575—Software application
    • H04Q3/54591—Supervision, e.g. fault localisation, traffic measurements, avoiding errors, failure recovery, monitoring, statistical analysis

Definitions

  • the present invention relates to a circuit arrangement for telecommunications switching systems, particularly telephone switching systems, comprising central and/or sub-central information-processing sequential logic systems having a limited call-handling capacity with respect to the information processing capacity.
  • the systems also comprise traffic measuring devices for identifying the information processing traffic load of a respective sequential logic system and for the recognition of information processing traffic overloads caused by processing requests. Requests nonacceptance devices serve for defense against such overloads in which a critical limit value can be set based on the measure of the respectively identified information processing traffic load.
  • Different degrees of urgency of various types of processing requests have analogous different urgency values individually assigned thereto and, on the basis of a respective comparison of the urgency value of each processing requests to the critical limit value, an acceptance character or a nonacceptance character is assigned when the urgency value is greater, or smaller, than the critical limit value.
  • Each of the processing requests for incoming information are supplied to the sequential logic system for processing in accordance with the appertaining character which has been assigned thereto (or not assigned thereto), whereby above-average urgency processing requests are considered with a certain priority over below-average urgency processing requests in view of the processing in the sequential logic system.
  • the German published application 3,416,074 discloses a circuit arrangement of the type set forth above. Given a heavier traffic load of the central sequential logic system due to processing requests which makes non-acceptance measures necessary, this circuit arrangement makes it possible to handle these according to the respective degree of urgency, i.e. makes it possible for some of them to still be accepted, but for the rest not to be accepted.
  • the urgency degrees of the connection-associated switching facilities have urgency values assigned thereto which are respectively associated to the processing request output by a connection-associated switching facility to the appertaining information-processing sequential logic system when the former is seized.
  • Dependent on the critical limit value which is set in the request nonacceptance device the appertaining processing request is still accepted or rejected according to the measure of this limit value by way of a respective comparison of the urgency vale to the limit value.
  • connection-associated switching facilities can be subscriber line circuits and connector sets. The latter can be prioritized over the subscriber line circuits. This would mean that, given a certain degree of traffic load, processing requests which come from connector sets would still be accepted but no processing requests deriving from subscriber line circuits would be accepted.
  • the connection-associated switching facilities can also be differentiated into more than two classes and the urgency degrees assigned thereto can also be multiply graduated in accordance with the manner set forth. For the connection-associated switching facilities of a lowest urgency degree (or of a plurality of lowest urgency degrees), this means that the subscribers affected by an increased traffic load and correspondingly more intense non-acceptance measures still have a certain chance for a call set up, particularly in view of the possibility of making emergency calls.
  • a repetition of seizure attempts by a subscriber undertaken in particularly brief time intervals should therefore not provide the subscriber with any greater chance or, at most, with only a slightly greater chance for a successful connection set up attempt. "Pushiness" should therefore not be rewarded and influencing the subscriber behavior in this direction should be avoided.
  • the above object is achieved in that switching devices provided in a greater plurality which output the processing requests with the same degree of urgency and to which identical urgency values are assigned by way of their addresses are additionally marked by an ordering value likewise derived from the address, being additionally marked therewith when they output a respective processing request.
  • the urgency values assigned to the processing requests are varied by the ordering values which expand the same, whereby connection requests having originally identical urgency are divided into urgency groups having urgency classifications of different values differing per urgency value.
  • the non-acceptance devices employ the respective urgency classification in the comparison to their critical limit value.
  • the assignment of the plurality of urgency classifications per urgency value to the ordering values is cyclically interchanged in uniform time intervals.
  • connection requests affected by non-acceptance measures and, therefore, the subscribers outputting the connection requests are combined in a plurality of groups to which urgency classifications are assigned such in a cyclically alternating chronologically uniform tempo that these groups are alternately mutually prioritized in sequence by their continuously changing urgency classifications.
  • urgency classifications such in a cyclically alternating chronologically uniform tempo that these groups are alternately mutually prioritized in sequence by their continuously changing urgency classifications.
  • one of these groups can be prioritized over all other such groups, in the next phase the further such group can be prioritized, etc, in a cyclical and chronologically uniform, progressive alternation.
  • the exemplary embodiment illustrated on the drawing shows portions of a circuit arrangement of telephone switching technology which is presumed known in terms of its many possibilities of construction It will be assumed that the present case involves a centrally-controlled telephone switching system in which all of the control events, for example connection set-up events, are centrally or subcentrally controlled. It is also assumed that a central or subcentral information-processing sequential logic system P serves for sequencing such events. Of course, this has limited call-handling capacity with respect to the information processing capacity.
  • connection-associated switching device T is shown in the upper portion of the drawing. In fact, connection-associated switching devices are present in a great number. These connection-associated switching devices can be a matter of subscriber line circuits, selection receiving sets, connector sets, terminator circuits of local trunks and long-distance trunks and the like. In case the telephone switching system is constructed in pulse code modulation (PCM) technology, the connection-associated switching device T constitutes ports in the interface groups. More detailed interrelationships regarding this structure are set forth in the description of the digital switching system EWSD in the supplement to the periodical "telcom report", 1981, (background material) as well as in U.S. Pat. No. 4,564,725, fully incorporated herein by this reference.
  • PCM pulse code modulation
  • connection-associated switching device T Information which are to be processed arrive into the connection-associated switching device T. This is thereby a matter of all switching identifiers which are output by subscriber stations from which subscribers intend to establish connections.
  • the analogous case applies to connection-associated switching devices which are not subscriber associated, for example, connector sets, terminator circuits and the like.
  • the aforementioned German published application discloses detailed particulars regarding the task of processing incoming information.
  • connection-associated switching device T All of the information coming into the connection-associated switching device T are to be processed by the sequential logic system P which, as already indicated, can also be multiply provided. In a manner known per se, these information are continuously interrogated with the assistance of scan events and are called in from the connection-associated switching device T by the sequential logic system P.
  • the information processing traffic load of the sequential logic system P is continuously measured with known traffic measuring devices. This therefore involves the load of the sequential logic system P with request for processing information arriving into the connection-associated switching device T.
  • a central sequential logic system P can also be burdened with information processing requests which have some other origin, for example for routine checks within the sequential logic system itself, and the like.
  • the traffic measuring devices which are presumed here to be known, therefore serve for the identification of the information processing traffic load of the sequential logic system P. This serves for the recognition of information processing traffic overloads caused by processing requests
  • Each information which has arrived in a connection-associated switching device T and which is to be processed results in a processing request which is directed to the sequential logic system P.
  • measures for defense in such overloads are initiated.
  • Request non-acceptance devices are provided for this purpose, these seeing to it that an excess of incoming information to be processed are not accepted.
  • Corresponding connections in the process of being set up are, accordingly not completed; in a known manner, the appertaining, dialing subscriber receives a busy signal
  • a request non-acceptance device only have to exercise their effect when the information processing traffic load of the sequential logic system P becomes too high.
  • a request non-acceptance device must reject more or less all of the incoming information processing requests
  • the degree of the load or, respectively, overload of the sequential logic system P is the determining factor for a percentage of processing requests to be rejected.
  • a critical limit value is adjustable in a request non-acceptance device based on the measure of the respectively identified information processing traffic load. This critical limit value indicates what proportion of the total number of processing requests directed to the sequential logic system P is to be rejected.
  • the urgency of the various processing requests is taken into consideration in the non-acceptance of processing requests.
  • connection set up it is advantageous to prefer information processing requests for connection set-up events based on the measure of a respective degree of progress which has already been achieved in the respective connection set up and, accordingly, to preferably undertake rejections, insofar as required, in processing requests which relate to information processing events of connections which are still at the beginning with respect to establishment of a connection.
  • connection set-up events for outgoing connections over connection set-up events for incoming connections Accordingly, processing requests of the various types can be equipped with appropriately different urgency degrees. Accordingly, different urgency values are individually assigned to these processing requests which differ in urgency.
  • the different degrees of urgency of different types of processing requests can also be casually conditioned by different subscriber connection privileges.
  • subscriber stations can also have a special connection privilege compared to a normal connection privilege, this special privilege giving them priority over the subscriber stations having normal connection privilege in the establishment of the connection.
  • there can also be catastrophe-prioritized subscriber stations which are, in turn, serviced with a priority over all other subscriber stations in setting up of connections.
  • the different urgency degrees of different types of processing requests derive from the different subscriber privileges which are stored for the appertaining subscribers.
  • a request non-acceptance device then functions in such a manner that it undertakes a comparison of the urgency value of each processing request to a critical limit value.
  • the drawing illustrates a request non-acceptance device K. Processing requests are supplied thereto via a path k. For each processing request, the request non-acceptance device K emits an acceptance character or a rejection character to the sequential logic system P by way of a path L, whereby the sequential logic system P is initiated to accept the appertaining processing request or to reject the same, i.e. to accept the appertaining information to be processed and process the same in a known manner or to transmit a corresponding, contradictory signal via a path t to the connection-associated switching device T, whereby it is signaled that the appertaining connection set up cannot be continued. An appropriate busy signal is sent the calling subscriber in a known manner.
  • a traffic measuring device At with whose assistance a critical limit value is continuously identified, this being accepted in a memory b1-b8 of the request non-acceptance device.
  • a memory b1-b8 of the request non-acceptance device In this storage one of the memory rows b1-b8 receives a corresponding marking. Accordingly, a respective one of eight different possible critical limit values may be stored.
  • the respective urgency value corresponding to a processing request is supplied to an urgency value intermediate memory D which likewise contains eight memory rows d1-d8.
  • the respective urgency value likewise is storable in one of the memory rows of the urgency value intermediate memory D and is correspondingly marked.
  • the request non-acceptance device further comprises a comparator K which, after arrival of each processing request, compares the urgency value assigned thereto and intermediately stored in the urgency value intermediate memory D to the stored, critical limit value.
  • the comparator K When the urgency value is greater than the critical limit value, the comparator K emits an acceptance character to the sequential logic system P.
  • the comparator K When the urgency value is lower than the critical limit value, the comparator K emits a rejection character to the sequential logic system P.
  • the comparator K therefore, assigns one of the two characters to each processing request, whereby each of the processing requests for incoming information is supplied to the sequential logic system P for processing or is not supplied thereto in accordance with the appertaining character which has been assigned. The possibility is thereby established that above-average urgency processing requests are taken into consideration with a certain priority over below-average urgency processing requests with respect to their processing in the sequential logic system P.
  • processing requests are output with different urgency values.
  • the processing requests are mutually prioritized based on the measure of the respective urgency degree.
  • a phase of throttling the traffic load i.e. when some of the incoming processing requests are rejected, this means that an extremely high proportion of processing requests having a low urgency degree are rejected
  • This requirement is caused by the emergency call possibility which must be established at any time.
  • the described priority should be guaranteed in the phases when the processing requests are rejected.
  • connection-associated switching devices provided in a greater plurality from which the processing requests are output with identical urgency degree and to which identical urgency values are assigned by way of their addresses are additionally marked by an ordering value likewise derived from the address, being additionally marked in this manner upon respective emission of a processing request.
  • Each of the connection-associated switching devices is selectable with the assistance of an address.
  • the appertaining address is present in the sequential logic system P.
  • this address is supplied to an address evaluator A. This derives the respective urgency value from the respective address.
  • the urgency value can also be additionally defined by the respective type of information to be processed.
  • the address evaluator A Given output of a respective processing request, the address evaluator A additionally derives an ordering value from the respective address of the connection-associated switching device. Let this be composed of the two last bits of a substantially more extensive address information.
  • the processing requests having the same urgency value are therefore additionally marked by this ordering value which is acquired with the assistance of a address evaluator A.
  • These ordering values partly differ from one another. They are uniformly distributed to the different processing requests, whereby one and the same ordering value continuously reappears, this being true of each of the different ordering values.
  • the urgency values assigned to the processing requests are therefore varied by the ordering values which augment the same. Connection requests originally having the same urgency are thereby divided into urgency groups having different urgency classifications of the different value per urgency value.
  • the urgency value assigned to each incoming processing request is temporarily stored in the urgency value intermediate memory D.
  • the urgency value of the processing requests are varied by the ordering values augmenting the same, the urgency classification deriving by the addition of the ordering value is respectively stored in the urgency value intermediate memory D instead of the urgency value.
  • an ordering value augmenting the respective urgency value is identified for certain processing requests with the assistance of the address evaluator A.
  • This ordering value is supplied to a combinational logic system V.
  • a time-of-day (TOD) generator U is also provided, the momentary time of day being stored therein in binary-encoded form.
  • the memory cells un--ul serve this purpose. Each of these memory cells serves for the storage of one bit of the time-of-day information. It is assumed that the memory cells u1 and u2 are provided for the last two place values of the respective time-of-day information. Accordingly, the information in the memory cell ul changes most frequently and that in the memory cell u2 changes with the second highest frequency.
  • the combinational logic circuit V then combines the ordering value of a processing request with those portions of the time-of-day information stored in the two memory cells u1 and u2.
  • This combination for example, can occur in the form of a simple ANDing.
  • an assignment of the plurality of urgency classifications per urgency value to the ordering values is achieved which cyclically changes in a time-dependent manner.
  • the assignment of the plurality of urgency classifications per urgency value to the ordering values is therefore cyclically interchanged in uniform time intervals.
  • the various subscribers from the processing request initially arrive having the same urgency value have urgency classifications which cyclically change in uniform time intervals.
  • the non-acceptance devices use the urgency classification insofar as such a classification is acquired in addition to the given urgency value.
  • the urgency classification is additionally acquired in the manner set forth for processing requests which have a relatively low urgency degree, particularly those to which the lowest urgency value is assigned.
  • the comparator K compares the respective urgency value or respectively, the respective urgency classification to the critical limit value. It can be provided that the different frequency values and the different urgency classifications are always equal to the critical limit value which has been set. This can be accomplished in that the critical limit values can also be only uneven numbers, whereas urgency values and urgency classifications can always be only even values In that case where the respective urgency value or the respective urgency classification can also be equal to the critical limit value which has been set, it is provided that an acceptance character is likewise assigned to the processing requests given equality. In contrast thereto, it can also be provided that a rejection character is assigned to the appertaining processing requests in this case.

Landscapes

  • Engineering & Computer Science (AREA)
  • Signal Processing (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Monitoring And Testing Of Exchanges (AREA)
  • Telephonic Communication Services (AREA)
  • Exchange Systems With Centralized Control (AREA)
  • Data Exchanges In Wide-Area Networks (AREA)
  • Computer And Data Communications (AREA)
  • Traffic Control Systems (AREA)
US06/896,253 1985-08-14 1986-08-13 Circuit arrangement for telecommunications switching systems, particularly for telephone switching systems comprising information-processing sequential logic systems and traffic measuring devices Expired - Lifetime US4802205A (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE3529168 1985-08-14
DE3529168 1985-08-14

Publications (1)

Publication Number Publication Date
US4802205A true US4802205A (en) 1989-01-31

Family

ID=6278511

Family Applications (1)

Application Number Title Priority Date Filing Date
US06/896,253 Expired - Lifetime US4802205A (en) 1985-08-14 1986-08-13 Circuit arrangement for telecommunications switching systems, particularly for telephone switching systems comprising information-processing sequential logic systems and traffic measuring devices

Country Status (4)

Country Link
US (1) US4802205A (de)
EP (1) EP0213408B1 (de)
AT (1) ATE50101T1 (de)
DE (1) DE3668742D1 (de)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5325426A (en) * 1991-04-23 1994-06-28 Siemens Aktiengesellschaft Method for overload prevention in a switching center of a communications network
US5425086A (en) * 1991-09-18 1995-06-13 Fujitsu Limited Load control system for controlling a plurality of processes and exchange system having load control system
US5574770A (en) * 1993-12-21 1996-11-12 Electronics And Telecommunications Research Institute Method for controlling overload of main processor of distributed switching system with hierarchy structure

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CA1310731C (en) * 1988-04-30 1992-11-24 Mamoru Higuchi Exchange system having originating call restriction function

Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3517123A (en) * 1967-11-24 1970-06-23 Bell Telephone Labor Inc Scanner control means for a stored program controlled switching system
JPS5690692A (en) * 1979-12-24 1981-07-22 Nec Corp Signal processing system of electronic switch board
EP0104637A2 (de) * 1982-09-29 1984-04-04 Siemens Aktiengesellschaft Schaltungsanordnung für Fernmeldeanlagen, insbesondere Fernsprechvermittlungsanlagen mit zentralen Informationsverarbeitungseinrichtungen mit Überlastsignalaussendung
EP0121239A2 (de) * 1983-03-31 1984-10-10 Siemens Aktiengesellschaft Schaltungsanordnung für Fernmeldeanlagen, insbesondere Fernsprechvermittlungsanlagen, mit informationsverarbeitenden Schaltwerken und Einrichtung zur Abwehr von Überbelastungen
US4497979A (en) * 1984-01-27 1985-02-05 At&T Bell Laboratories Method for processing essential lines in a communication system
EP0166101A1 (de) * 1984-04-30 1986-01-02 Siemens Aktiengesellschaft Schaltungsanordnung für Fernmeldevermittlungsanlagen, insbesondere Fernsprechvermittlungsanlagen, mit informationsverarbeitenden Schaltwerken und Verkehrsmesseinrichtungen
US4564725A (en) * 1983-03-31 1986-01-14 Siemens Aktiengesellschaft Telecommunications system, particularly a telephone exchange system, having overload protected sequential logic systems
US4649234A (en) * 1984-07-26 1987-03-10 Siemens Aktiengesellschaft Circuit arrangement for telecommunications exchange systems, particularly telephone exchange systems, comprising information processing sequential logic systems and traffic measuring devices

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3517123A (en) * 1967-11-24 1970-06-23 Bell Telephone Labor Inc Scanner control means for a stored program controlled switching system
JPS5690692A (en) * 1979-12-24 1981-07-22 Nec Corp Signal processing system of electronic switch board
EP0104637A2 (de) * 1982-09-29 1984-04-04 Siemens Aktiengesellschaft Schaltungsanordnung für Fernmeldeanlagen, insbesondere Fernsprechvermittlungsanlagen mit zentralen Informationsverarbeitungseinrichtungen mit Überlastsignalaussendung
EP0121239A2 (de) * 1983-03-31 1984-10-10 Siemens Aktiengesellschaft Schaltungsanordnung für Fernmeldeanlagen, insbesondere Fernsprechvermittlungsanlagen, mit informationsverarbeitenden Schaltwerken und Einrichtung zur Abwehr von Überbelastungen
US4564725A (en) * 1983-03-31 1986-01-14 Siemens Aktiengesellschaft Telecommunications system, particularly a telephone exchange system, having overload protected sequential logic systems
US4497979A (en) * 1984-01-27 1985-02-05 At&T Bell Laboratories Method for processing essential lines in a communication system
EP0166101A1 (de) * 1984-04-30 1986-01-02 Siemens Aktiengesellschaft Schaltungsanordnung für Fernmeldevermittlungsanlagen, insbesondere Fernsprechvermittlungsanlagen, mit informationsverarbeitenden Schaltwerken und Verkehrsmesseinrichtungen
US4649234A (en) * 1984-07-26 1987-03-10 Siemens Aktiengesellschaft Circuit arrangement for telecommunications exchange systems, particularly telephone exchange systems, comprising information processing sequential logic systems and traffic measuring devices

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
Telcom Report, 1981, pp. 1 83. *
Telcom Report, 1981, pp. 1-83.

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5325426A (en) * 1991-04-23 1994-06-28 Siemens Aktiengesellschaft Method for overload prevention in a switching center of a communications network
US5425086A (en) * 1991-09-18 1995-06-13 Fujitsu Limited Load control system for controlling a plurality of processes and exchange system having load control system
US5574770A (en) * 1993-12-21 1996-11-12 Electronics And Telecommunications Research Institute Method for controlling overload of main processor of distributed switching system with hierarchy structure

Also Published As

Publication number Publication date
ATE50101T1 (de) 1990-02-15
EP0213408B1 (de) 1990-01-31
DE3668742D1 (de) 1990-03-08
EP0213408A1 (de) 1987-03-11

Similar Documents

Publication Publication Date Title
US3557315A (en) Automatic telecommunication switching system and information handling system
US4757529A (en) Call distribution arrangement
US5216669A (en) Method for setting up virtual connections in switching equipment operating according to an asynchronous transfer mode
CA1253243A (en) Telecommunications exchanges allocating variable channel bandwidth
US3271521A (en) Circuit arrangement for ascertaining operating conditions of subscriber stations of a time multiplex communication system
US3963872A (en) Non-symmetric folded four-stage switching network
US5325426A (en) Method for overload prevention in a switching center of a communications network
US3700819A (en) Time division switching system with time slot interchange
US4626624A (en) Telecommunications system, particularly a telephone exchange system, having overload protected sequential logic systems
US4626625A (en) Telecommunications system, particularly a telephone exchange system, having overload protected sequential logic systems
US4802205A (en) Circuit arrangement for telecommunications switching systems, particularly for telephone switching systems comprising information-processing sequential logic systems and traffic measuring devices
US4390982A (en) Digital PBX system
US3754100A (en) Age time connection network arrangement adapted to be used more particularly in telephone switching
US5469543A (en) Policing circuits arranged in matrix array for selectively transferring virtual path identifier (VPI) responsive to either VPI or service class identifier (SCI) threshold value
US3334191A (en) Electronic queuing system having recall, intercept and priority means
US3691301A (en) Switching system arranged for time restricted flat rate station-to-station toll calling
US3268667A (en) Electronic switching telephone system
US4096356A (en) Call restriction arrangement
US3274342A (en) Common channel communication system conference circuit
US4564725A (en) Telecommunications system, particularly a telephone exchange system, having overload protected sequential logic systems
US4649234A (en) Circuit arrangement for telecommunications exchange systems, particularly telephone exchange systems, comprising information processing sequential logic systems and traffic measuring devices
US3760105A (en) Traffic monitor for data processing system
US3627951A (en) Asynchronous communications system controlled by data processing device
US3296377A (en) Time multiplex telephone system with multi-frequency dialing
US4860344A (en) Circuit arrangement for telecommunications switching systems, particularly telephone switching systems, etc.

Legal Events

Date Code Title Description
AS Assignment

Owner name: SIEMENS AKTIENGESELLSCHAFT, A CORP. OF GERMANY, GE

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:EDER, MICHAEL;LEUTNER, KLAUS;POHL, SIEGFRIED;REEL/FRAME:004642/0527

Effective date: 19860807

STCF Information on status: patent grant

Free format text: PATENTED CASE

FEPP Fee payment procedure

Free format text: PAYOR NUMBER ASSIGNED (ORIGINAL EVENT CODE: ASPN); ENTITY STATUS OF PATENT OWNER: LARGE ENTITY

FPAY Fee payment

Year of fee payment: 4

FPAY Fee payment

Year of fee payment: 8

FPAY Fee payment

Year of fee payment: 12